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| Properties of Bases |
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| Taste |
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| Bases are bitter to taste. |
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| Feel |
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| They are soapy and slippery to touch. |
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| Electrical Conductivity |
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| Some bases are good conductors of electricity. For e.g., soluble bases like sodium hydroxide and potassium hydroxide are used as electrolytes. |
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| Corrosive Action |
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| Strong alkalis like sodium hydroxide and potassium hydroxide are highly corrosive or caustic in nature. Sodium hydroxide and potassium hydroxide are commonly called caustic soda and caustic potash respectively. Organic tissues like skin, etc. get completely corroded by these two alkalis. However, the other alkalis are only mildly corrosive. |
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| Action with Air |
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| When exposed to air, alkalis combine with the carbon dioxide of the air, to form the respective carbonate. |
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| An application of an alkali reacting with carbon dioxide is the drying of lime i.e. white washing. The white washing of walls is due to the action of carbon dioxide of the air on calcium hydroxide. When milk of lime, a watery paste of calcium hydroxide, is applied on a wall, it reacts with the carbon dioxide of the air to form a white layer of calcium carbonate. |
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| Action with Ammonium Salts |
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| Alkalis combine with ammonium salts to liberate ammonia. |
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Alkali + Ammonium salt  Salt + Water + Ammonia |
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| Action with Acids |
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| Bases combine with acids to form salt and water only. |
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| Base + Acid Salt + Water |
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